Our working hypothesis is that enamel proteins play a central role in the process of amelogenesis and a determination of their number, structure, localization and sequence of appearance and disappearance in enamel organ cells and extracellular matrix enamel formation is essential to an understanding of that process. With presently available techniques, solubilized enamel proteins can be divided into two classes of proteins, amelogenins and enamelins, containing a total of 15 to 25 components. It is not known whether each of these components represents the product of an individual gene, or whether the multiple components are derived from the physiologic breakdown of a limited number of proteins or artefacts produced during the extraction procedures. The overall objective of this proposal is to develop monoclonal and monospecific antibodies to various epitopes within enamel proteins and to use these: (1) to determine chemical and immunological interrelationships between the proteins in order to develop a model which accounts for the marked apparent heterogeneity of the enamel proteins, (2) to determine the distribution and localization of specific enamel proteins in relations to the structure of enamel matrix and associated cells during tooth development, (3) to determine the structural relation of specific protein to hydroxyapatite crystal growth during secretion and maturation of enamel mitrax. State of the art techniques in immunology, protein chemistry and light microscopy will be employed to achieve the objectives. The information gained from these studies may ultimately (1) lead to a better understanding of the functions of enamel proteins, (2) lead to an explanation of some genetic defects affecting the enamel matrix, (3) lead tothe development of more effective and biologically compatible restorative materials.